i saw before that there was a way to figure out how much a light will cost to run. Does anyone know how to figure it out. IM running a 400 watt HPS light. nvm i found the answer
i had the same problem, you multiply 18hous per the wattage of your light.... you will get 18*400*30=216000watt=216kW nos you go to your copanys page and see how much you pay per kW lol i pay around €16 during veg a month i got a 250